Flasher switch



Feb. 23, 1943 Y c, ADLER, JR 2,311,921

FLASHER SWITCH Fil ed Aug. 8, 1941 I gwucm ioz.

Ch wales dialer; Jr;

Patented F eb. 23, 1943 UNITED STATES PATENT OFFICE FLASHER, SWITCHCharles Adler, Jr., Baltimore, Md.

Application August 8, 1941, Serial No. 406,037 3 Claims. (01. 200-81)The present invention relates to relays of the flasher type andoperating means therefor. The invention is particularly useful foroperating a flashing type of airplane tail lamp as described in myPatent 2,265,095, dated December 2, 194.1.

The principal object of the invention is to provide a simple andreliable means for operating a relay without recourse to eitherelectro-magnetic means which frequently interfere with radiotransmission and reception now a necessary part of most air craft or tothermal means which are affected by temperature changes to causevariation of the timing sequence.

A further object of the invention is to provide a construction which canbe located in a part of the airplane remote from the location of thetail light or other light and which can be operated from the airplanemotor or a separate prime mover or by means of a Venturi aspirating orsuction system disposed in the slip stream of the propeller.

Another object of the invention is to provide a construction which isappropriately positioned to be operative regardless of the position ofthe airplane so that the plane may be maneuvered at will without dangerof disrupting the relay for controlling periodic flashing of the taillight or other illuminating means.

The construction illustrated may be modified in various ways and it isto be understood that While I have illustrated the preferred forms ofthe invention, the use of gas operated means for controlling the relaymay be carried out, using other types of operating structures.

Referring to the drawing:

Figure 1 is a diagrammatic view of one form of the invention;

Figure 2 is a diagrammatic view of the same form of the invention inwhich instead of relying on a Venturi-aspirator or suction means forreducing the pressure in the sealed chamber in which the parts arelocated, a suitable vacuum pump is interposed in the line to accomplishthe result and operated from the motor of the plane or independently bya separate prime mover;

Figure 3 is a modification showing the manner in which a plurality ofcontact members may be operated to open and close electrical circuitsfor predetermined time intervals, and

Figure 4 is a detail plan view of Figure 3, with parts in section.

worm I9 which engages a large worm gear 20 carried on the shaft 2| andwhich shaft, in turn, carries a worm 22 for engaging the large gear 23which is mounted for rotation on a shaft 25. Fixed to the shaft 25 is aninsulating disc 26 having an insulated cam 21. The peripheral dimensionsof the cam 21 and of the uncammed portion of disc 26 are substantiallyequal but may be varied as desired. Three spring contact members areemployed in the construction shown in Figure 1 which are respectivelynumbered 30, 3|, and 32. The flexible spring contact finger 31 leadsthrough an insulating block 34 sealed in the housing and is connected bya wire 35 which leads through the switch 36 and battery 31 to the commonwire 38. The contact fingers 30 and 32 are similarly supported in thesealed insulating block 34 and are connected by the wires 39 and 40respectively to a pair of lamps 4| and 42.

In order to rotate the rotor [3, a jet tube 43 is supported in thehousing l0 so that its larger end 44 is open to the atmosphere while itssmaller end 45 is projected in the path of rotation of the vanes on theperiphery of the rotor l3. Preferably at the bottom of the casing,although it may be located in the sides or top, is a pipe 46 which inthe construction shown in Figure 1, communicates with the smaller end 41of a Venturi device 48. This Venturi structure 41-48 is disposed in theslip stream of the propeller and the reduced end 41 of the Venturi has avent 49 whereby in the travel of the plane, air will rush at highvelocity through said vent and since the end of the pipe 46 ispositioned at this point of high velocity and low pressure, the chamberI?! will be continuously evacuated by the suction created in much thesame manner as a vacuum pump or aspirating device. The pressure in thechamber [0 is continuously being reduced to such an extent that air isbeing drawn through the jet 43 continuously and impinges upon the vanesof the rotor 13 at a pressure whereby the same is caused to rotate at ahigh speed which may be 9,000 R. P. M. The rotation of the rotor will,because of the mechanism heretofore described, cause the gear 23 torotate and with it the shaft 25 and the cam 21. During one period ofrotation of the shaft 25, the cam 21 will engage the contact finger 3|to move the same into contact with the finger 30 to thereby illuminatethe lamp 41 which, for instance, may give a white beam and when the cam21 is disengaged from the contact finger 3|, it normally moves intocontact with the contact finger 32 whereby the lamp 42 is illuminatedand this may give a green or red beam.

The peripheral length of the cam 21 may be so regulated that theinterval of time that the lamps are respectively flashed is readilycontrollable; usually the peripheral length of the cam 21 is equal toabout one-half the peripheral dimension of the disc 26 so that the lampswill and the peripheral dimensions of the cam and disc. In other Words,the transmission reduction gearing is constructed and arranged to causethe lamps 4i and 42 to be alternately or intermittently lit for apredetermined interval as determined by the length of the cam 21 andmakes allowance for variations in the speed condition of the plane aswell as wind velocity. Thus variable means are provided to insure auniform rate of flashing and not a continuous illumination of the lampswhich might take place if the disc 26 were allowed to rotate at a highspeed.

The pipe 46 is preferably positioned to communicate the suction meanswith the interior of the housing ll] on the side opposite the jet tube43 and adjacent the rotor l4, so that the air upon impinging on thevanes of the rotor, is immediately withdrawn from the housing and is notallowed to circulate therein, since, if it were, the air and foreignmatter entrained therewith might interfere with the operation of thetransmission gearing and its associated parts.

It will be observed that the operation of the relay is wholly conductedwithout the inclusion of electromagnetic means which have been found toproduce an inductive effect frequently objectionable in that it impairsradio transmission and reception. Also, this invention eliminates thevariables occasioned by the eifect of temperature changes on relayshaving thermal means.

Referring to Figure 2, instead of having a Venturi-aspiratorconstruction, a vacuum pump 50 is connected to the line 46 and thisvacuum pump may be operated from the airplane engine or a separatemotor, not shown, to continuously maintain the required reduced pressurein the chamber l0.

Referring to Figure 3, I have illustrated a construction which will beuseful where more than two lamps are to be flashed. In thisconstruction, the shaft is extended in the form of a cam shaft 5|. Thespring contact fingers 30, 32 and 52 are suitably supported in theinsulated block 34' and when engaged by one of the cams 53, 54

or 55, will be moved into contact with one of the contacts 56 carried bythe plate 5'! respectively so that contact will be made to one of thelamps for a proper time interval consecutively. The common wire 38 isconnected through the battery 3! and switch 36 by a wire to the plate 51and the spring contact fingers 39, 32' and 52 are connected by wires 58,59 and 60 respectively to the lamps 6 I, 62 and 63 which are to beilluminated. The lamps may be colored red, green and white or clear.

It will be understood that the fluid pressure operated rotor may take avariety of forms as may also the jet pipe 43 .and the exhaustingapparatus, the particular requirement being, however, that a lightweightreliable construction be provided having a relatively feW parts in whichconventional electric relay mechanisms, such as electromagnetic means orthermal means are eliminated.

Iclaim':

1. An apparatus for aircraft comprising a housing, a rotor having vanesmounted in said housing, a jet tube extending into the housing, saidtube communicating at one end with the atmosphere and having its otherend disposed to direct a stream of air upon the vanes of said rotor torotate the same at high speed when the aircraft is in flight, electricalcontact members connected to electrical circuits to open and close thesame, ca-m means in said housing for controlling the operation of saidcontact members, reduced transmission gearing operatively connected tosaid rotor and said cam means for operating the electrical contactmembers upon rotation of the rotor alternately to open and close saidelectrical circuits, and means for maintaining a reduced pressure insaid housing, said last mentioned means being positioned relative to thejet tube to immediately withdraw the air after it impinges on the vanesof the rotor so that the air entering the housing does not interferewith the operation of the other parts therein.

2. An apparatus for aircraft comprising a housing, a rotor having vanesmounted in said housing, a jet tube extending into the housing, saidtube communicating at one end with the atmosphere and having its otherend disposed to direct a stream of air upon the vanes of said rotor torotate the same at high speed when the aircraft is in flight, electricalcontact members connected to electrical circuits to open and close thesame, cam means in said housing for controlling the operation of saidcontact members, reduced transmission gearing operatively connected tosaid rotor and said cam means for operating the electrical contactmembers upon rotation of the rotor alternately to open and close saidelectrical circuits, and suction means communicating with the housing onthe sides opposite to said jet tube for maintaining a reduced pressurein the housing for withdrawing the air after it impinges on the vanes ofthe rotor so that the air entering the housing does not interfere withthe operation of the other parts therein.

3. An apparatus for aircraft comprising a housing, a rotor having vanesmounted in said housing, a jet tube extending into the housing, saidtube communicating at one end with the atmosphere and having its otherend disposed to direct a stream of air upon the vanes of said rotor torotate the same at high speed when the aircraft is in flight, electricalcontact members connected to electrical circuits to open and close thesame, cam means in said housing for controlling the operation of saidcontact members, reduced transmission gearing operatively connected tosaid rotor and said cam means for operating the electrical contactmembers upon rotation of the rotor alternately to open and close saidelectrical circuits, a venturi having its smaller end extending in thedirection of travel of the aircraft, said venturi having a vent in thesmaller end thereof, and a pipe communicating the vent end of saidventuri with said housing adjacent the rotor so that the air passingthrough said vent at high velocity continuously sucks air from thehousing to reduce the pressure therein and causes the air to be drawnthrough the .jet tube and impinge on the vanes with a force sufiicientto rotate the rotor without circulating in the housing or interferingwith the operation of the other parts in the housing.

CHARLES ADLER, JR.

